diff --git a/left/src/key_scanner.c b/left/src/key_scanner.c
index fb89bd9..d8990ee 100644
--- a/left/src/key_scanner.c
+++ b/left/src/key_scanner.c
@@ -14,7 +14,7 @@ void InitKeyScanner(void)
     LPTMR_GetDefaultConfig(&lptmrConfig);
     LPTMR_Init(KEY_SCANNER_LPTMR_BASEADDR, &lptmrConfig);
 
-    LPTMR_SetTimerPeriod(KEY_SCANNER_LPTMR_BASEADDR, MSEC_TO_COUNT(KEY_SCANNER_INTERVAL_MSEC, LPTMR_SOURCE_CLOCK));
+    LPTMR_SetTimerPeriod(KEY_SCANNER_LPTMR_BASEADDR, USEC_TO_COUNT(KEY_SCANNER_INTERVAL_USEC, LPTMR_SOURCE_CLOCK));
     LPTMR_EnableInterrupts(KEY_SCANNER_LPTMR_BASEADDR, kLPTMR_TimerInterruptEnable);
     EnableIRQ(KEY_SCANNER_LPTMR_IRQ_ID);
     LPTMR_StartTimer(KEY_SCANNER_LPTMR_BASEADDR);
diff --git a/left/src/key_scanner.h b/left/src/key_scanner.h
index a871d48..11906b5 100644
--- a/left/src/key_scanner.h
+++ b/left/src/key_scanner.h
@@ -1,6 +1,10 @@
 #ifndef __KEY_SCANNER_H__
 #define __KEY_SCANNER_H__
 
+// Includes:
+
+    #include "main.h"
+
 // Macros:
 
     #define LPTMR_SOURCE_CLOCK CLOCK_GetFreq(kCLOCK_LpoClk)
@@ -9,7 +13,7 @@
     #define KEY_SCANNER_LPTMR_IRQ_ID   LPTMR0_IRQn
     #define KEY_SCANNER_HANDLER        LPTMR0_IRQHandler
 
-    #define KEY_SCANNER_INTERVAL_MSEC 1
+    #define KEY_SCANNER_INTERVAL_USEC (1000 / KEYBOARD_MATRIX_ROWS_NUM)
 
 // Functions: